Stenorhamphus segerak, Smith & Hwang & Weirauch, 2019

Smith, Samantha, Hwang, Wei Song & Weirauch, Christiane, 2019, Synonymy of Mangabea and Stenorhamphus, with the description of two new species (Hemiptera: Reduviidae: Emesinae: Collartidini), Raffles Bulletin of Zoology 67, pp. 135-149 : 145-148

Stenorhamphus segerak , new species

( Figs. 1 , 2 , 4 , 5A , 6 A–D, 7A, B, E–G)

Diagnosis. Recognised within Stenorhamphus by the relatively small total length (5.7 mm), two pairs of stout setae posterior to the eye, spines on the trochanter, fascicle of stout setae on the anterior area of the gena postocular region developed, posterior lobe of pronotum longer than anterior, almost covering metanotum, legs long, mid and hind coxae longer than length of abdomen, forecoxa extending past pronotum, two spines on posterior lobe of pronotum.

Description. Male: small (total length, holotype: 5.7 mm) COLOURATION: general colouration brown, with posterior pronotal lobe, pygophore, postocular region and wings darker brown, abdomen, forecoxa and anterior region of head yellowish ( Figs. 2A, B ). Head: postocular region dark brown with spots, anterior anteocular region yellow ( Figs. 4A, B ). Antenna: brown, flagellomeres light brown. Labium: light brown. Thorax: brown, posterior pronotum darker. Legs: Coxae light brown to yellow, trochanters, femora, tibiae, and tarsi pale brown. Wings: uniformly dark brown. Abdomen: tergites pale brown; mediosternites pale brown, laterosternites somewhat darker; pygophore dark brown. VESTITURE: as in genus description with the following differences: Head: ventral surface with four pairs of long, stout setae located posterior to antennifer, at anterior and posterior margins of eye ( Figs. 4A, B ), fascicle of more than twelve stout setae on gena ventrad of apex of maxillary plate ( Fig. 4B ), two pairs of stout setae dorsolaterally posterior to eye ( Fig. 4B ); second labial segment (first visible) with fascicle of medium-length stout setae on ventral surface in apical half of segment ( Fig. 4B ); Legs: posterodorsal series and four stout, long setae anteroventral, one stout, long seta posteroventral ( Figs. 4A, F ), foretrochanter with five stout setae on anterior surface ( Fig. 4A ), ventral surface of forefemur with about 13 medium and long, stout setae in basal 3/4, interspersed with short setae ( Fig. 4A ). STRUCTURE: as in genus description with the following differences: Head: ( Figs. 4A, B, H ): Eyes: globulose and subhemispheric in dorsal perspective ( Fig. 4A, H ), oval in lateral view, reaching dorsal surface of head, almost reaching ventral surface of head ( Figs. 4A, B ). Antenna: extremely long, slender; scapus (directed posteriad) surpassing hind coxa ( Figs. 2A, B ). Labium ( Figs. 4A, B ). Thorax ( Figs. 4F, G, H ): collar of pronotum pronounced, posterior lobe of pronotum slightly wider than long, distinctly wider than anterior lobe, slightly depressed medially and with raised, spined, lateral areas in posterior half of lobe, posterior margin concave (Figs. F, H). Mesoscutellum subrectangular, lateral edge a rounded ridge ( Fig. 4G ). Legs ( Figs. 4A, C, D ). Wings ( Figs. 5A ): basal cell trapezoidal, rmcu cross vein absent ( Fig. 5A ). Abdomen ( Figs. 2A, B , 4E ): Genitalia ( Figs. 6A, B, C, D , 7A, B, E, F, G ): pygophore elongate ovoid, with spine-like medial process, transverse bridge present ( Figs 6A, B, C, D ); parameres slender, curved, apex rounded ( Figs. 6A, B, C, D , 7B ); aedeagus ( Figs. 7A, F, G ) with basal plates stout and strongly curved, a relatively large capitulate process, ponticulus basilaris slender or nonexistent, basal plate extension relatively short ( Figs. 7A, F, G ), basal plate struts short ( Figs. 7A, G ), phallothecal sclerite curved, more heavily sclerotised anteriorly and posteriorly ( Fig. 7A ), endosoma with sclerotised ventral and lateral lobes with small spicules ( Fig. 7A ), lateral lobes long, phallosoma laterally with heavily sclerotised lobe, with short, stout spicules ( Fig. 7E ).

Measurements. See Table 1 .

Female. Unknown.

Etymology. Named after the collecting locality of the holotype at Nanga Segerak in Sarawak; a noun in apposition.

Distribution. Only known from the type locality.

Biology. Found in lowland dipterocarp forests at mid elevation.

Type material. Holotype: male, Malaysia, Sarawak, Lubok Antu District, Lanjak Entimau Wildlife Sanctuary, Nanga Segerak, 1.4200°N, 112.0044°E, 506 m, yellow pan trap, Hwang et al., 16–17 Oct 2017 [SW17 L46] ( RCW 5465), type currently deposited in National University of Singapore, Lee Kong Chian Natural History Museum, Zoological Reference Collection ( ZRC) .

Discussion. Most closely related to Stenorhamphus nubiferus and S. phuphan , with which this species shares the presence of a pair of ventral setae in position 5, lateral to the eye (9:1). Distinguished from these two species by the presence of a pair of ventral setae in position 4 (8:1) and a pair of spines on the posterior pronotal lobe (17:1).

Figures

Fig. 1. Phylogenetic hypothesis of Collartidini, based on morphological characters. Upper phylogeny: Fundamental parsimony tree, built using 25-character morphology matrix.Percentages above branches are jackknife support values (100 replications).As each fundamental tree differs only in relationships among Collartida, the first tree was arbitrarily chosen for jackknife analysis. Lower phylogeny: Strict consensus tree out of three equally parsimonious trees, with 11 Collartidini and 5 outgroup species. Numbers above branches refer to characters from morphology matrix, numbers below branches refer to character states. Synapomorphies for Collartidini and Stenorhamphus are listed.

Fig. 2. Dorsal and lateral habitus of the holotypes of Stenorhamphus segerak, new species and S. phuphan, new species. A, S. segerak, male, lateral (note four spines on head, spines along labium, spine on posterior lobe of pronotum, long coxa and antenna); B, S. segerak, male, dorsal (note spines on posterior lobe of pronotum, length of hemelytra, size of postocular region, length of posterior lobe of pronotum); C, S. phuphan, male, lateral (note ventral spines on head, length of mid and hind legs, general colouration); D, S. phuphan, male, dorsal (note long legs, postocular segment present).

Fig. 4. Stenorhamphus segerak details of head, legs and metanotum. Scale set to 0.5 mm unless otherwise specified. A, Head and thorax, lateral view (4 spines on forecoxa, spines along femur, trochanter spined); B, Head, lateral view (Four pairs of spines dorsally on head, two pairs laterally postocular, fascicle on apical portion of head, spines along labium, clypeus [cly], maxillary plate [mxpl], mandibular plate [mdpl], gena [ge], labrum [lr]); C, Foretarsus (simple); D, Midtarsus (simple); E, Spiracle on 6th abdominal segment; F, Head and pronotum, lateral view (Spine on posterior lobe of pronotum, evenly spaced hairs along antenna); G, Mesoscutellum (lateral edge rounded ridge, anterior portion sub-rectangular); H, Head, pronotum and metanotum dorsal view (pronotal spine [prs], clypeus, drop-shaped eyes).

Fig. 5. Stenorhamphus segerak and S. phuphan forewing. Anterior wing margin on the left. A, S. segerak forewing, Pcu vein present but not visible in image; B, S. phuphan forewing.

Fig. 6. Pygophores of Stenorhamphus segerak and S. phuphan in dorsal, ventral, posterior and lateral views. Scale set to 0.5 mm. A–D, S. segerak pygophore, dorsal, ventral, posterior, and lateral view respectively; E–H, S. phuphan pygophore, dorsal, ventral, posterior, and lateral view respectively.

Fig. 7. Paramere and phallus of Stenorhamphus segerak and S. phuphan in dorsal, ventral, posterior and lateral views. Scale set to 0.2 mm unless otherwise stated; A, S. segerak, phallus; capitate process (cp), basal plate (bp), basal plate extension (bpext), endosomal struts of aedeagus (est), endosomal lateral lobe (ell), dorsal phallothecal sclerite (dps); B, S. segerak paramere; C, S. phuphan paramere. D: S. phuphan phallus; basal plate (bp), basal plate extension (bpext), capitate process (cp), endosomla lateral lobe (ell), (est), endosomal ventral lobe (evl); E, S. segerak ventral phallotheca, spined; F, G, S. segerak dorsal, ventral phallus respectively; H, I, S. phuphan dorsal, ventral pygophore respectively.